1# SPDX-License-Identifier: GPL-2.0
2VERSION = 6
3PATCHLEVEL = 0
4SUBLEVEL = 0
5EXTRAVERSION = -rc1
6NAME = Hurr durr I'ma ninja sloth
7
8# *DOCUMENTATION*
9# To see a list of typical targets execute "make help"
10# More info can be located in ./README
11# Comments in this file are targeted only to the developer, do not
12# expect to learn how to build the kernel reading this file.
13
14$(if $(filter __%, $(MAKECMDGOALS)), \
15	$(error targets prefixed with '__' are only for internal use))
16
17# That's our default target when none is given on the command line
18PHONY := __all
19__all:
20
21# We are using a recursive build, so we need to do a little thinking
22# to get the ordering right.
23#
24# Most importantly: sub-Makefiles should only ever modify files in
25# their own directory. If in some directory we have a dependency on
26# a file in another dir (which doesn't happen often, but it's often
27# unavoidable when linking the built-in.a targets which finally
28# turn into vmlinux), we will call a sub make in that other dir, and
29# after that we are sure that everything which is in that other dir
30# is now up to date.
31#
32# The only cases where we need to modify files which have global
33# effects are thus separated out and done before the recursive
34# descending is started. They are now explicitly listed as the
35# prepare rule.
36
37ifneq ($(sub_make_done),1)
38
39# Do not use make's built-in rules and variables
40# (this increases performance and avoids hard-to-debug behaviour)
41MAKEFLAGS += -rR
42
43# Avoid funny character set dependencies
44unexport LC_ALL
45LC_COLLATE=C
46LC_NUMERIC=C
47export LC_COLLATE LC_NUMERIC
48
49# Avoid interference with shell env settings
50unexport GREP_OPTIONS
51
52# Beautify output
53# ---------------------------------------------------------------------------
54#
55# Normally, we echo the whole command before executing it. By making
56# that echo $($(quiet)$(cmd)), we now have the possibility to set
57# $(quiet) to choose other forms of output instead, e.g.
58#
59#         quiet_cmd_cc_o_c = Compiling $(RELDIR)/$@
60#         cmd_cc_o_c       = $(CC) $(c_flags) -c -o $@ $<
61#
62# If $(quiet) is empty, the whole command will be printed.
63# If it is set to "quiet_", only the short version will be printed.
64# If it is set to "silent_", nothing will be printed at all, since
65# the variable $(silent_cmd_cc_o_c) doesn't exist.
66#
67# A simple variant is to prefix commands with $(Q) - that's useful
68# for commands that shall be hidden in non-verbose mode.
69#
70#	$(Q)ln $@ :<
71#
72# If KBUILD_VERBOSE equals 0 then the above command will be hidden.
73# If KBUILD_VERBOSE equals 1 then the above command is displayed.
74# If KBUILD_VERBOSE equals 2 then give the reason why each target is rebuilt.
75#
76# To put more focus on warnings, be less verbose as default
77# Use 'make V=1' to see the full commands
78
79ifeq ("$(origin V)", "command line")
80  KBUILD_VERBOSE = $(V)
81endif
82ifndef KBUILD_VERBOSE
83  KBUILD_VERBOSE = 0
84endif
85
86ifeq ($(KBUILD_VERBOSE),1)
87  quiet =
88  Q =
89else
90  quiet=quiet_
91  Q = @
92endif
93
94# If the user is running make -s (silent mode), suppress echoing of
95# commands
96
97ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
98  quiet=silent_
99  KBUILD_VERBOSE = 0
100endif
101
102export quiet Q KBUILD_VERBOSE
103
104# Call a source code checker (by default, "sparse") as part of the
105# C compilation.
106#
107# Use 'make C=1' to enable checking of only re-compiled files.
108# Use 'make C=2' to enable checking of *all* source files, regardless
109# of whether they are re-compiled or not.
110#
111# See the file "Documentation/dev-tools/sparse.rst" for more details,
112# including where to get the "sparse" utility.
113
114ifeq ("$(origin C)", "command line")
115  KBUILD_CHECKSRC = $(C)
116endif
117ifndef KBUILD_CHECKSRC
118  KBUILD_CHECKSRC = 0
119endif
120
121export KBUILD_CHECKSRC
122
123# Use make M=dir or set the environment variable KBUILD_EXTMOD to specify the
124# directory of external module to build. Setting M= takes precedence.
125ifeq ("$(origin M)", "command line")
126  KBUILD_EXTMOD := $(M)
127endif
128
129$(if $(word 2, $(KBUILD_EXTMOD)), \
130	$(error building multiple external modules is not supported))
131
132$(foreach x, % :, $(if $(findstring $x, $(KBUILD_EXTMOD)), \
133	$(error module directory path cannot contain '$x')))
134
135# Remove trailing slashes
136ifneq ($(filter %/, $(KBUILD_EXTMOD)),)
137KBUILD_EXTMOD := $(shell dirname $(KBUILD_EXTMOD).)
138endif
139
140export KBUILD_EXTMOD
141
142# Kbuild will save output files in the current working directory.
143# This does not need to match to the root of the kernel source tree.
144#
145# For example, you can do this:
146#
147#  cd /dir/to/store/output/files; make -f /dir/to/kernel/source/Makefile
148#
149# If you want to save output files in a different location, there are
150# two syntaxes to specify it.
151#
152# 1) O=
153# Use "make O=dir/to/store/output/files/"
154#
155# 2) Set KBUILD_OUTPUT
156# Set the environment variable KBUILD_OUTPUT to point to the output directory.
157# export KBUILD_OUTPUT=dir/to/store/output/files/; make
158#
159# The O= assignment takes precedence over the KBUILD_OUTPUT environment
160# variable.
161
162# Do we want to change the working directory?
163ifeq ("$(origin O)", "command line")
164  KBUILD_OUTPUT := $(O)
165endif
166
167ifneq ($(KBUILD_OUTPUT),)
168# Make's built-in functions such as $(abspath ...), $(realpath ...) cannot
169# expand a shell special character '~'. We use a somewhat tedious way here.
170abs_objtree := $(shell mkdir -p $(KBUILD_OUTPUT) && cd $(KBUILD_OUTPUT) && pwd)
171$(if $(abs_objtree),, \
172     $(error failed to create output directory "$(KBUILD_OUTPUT)"))
173
174# $(realpath ...) resolves symlinks
175abs_objtree := $(realpath $(abs_objtree))
176else
177abs_objtree := $(CURDIR)
178endif # ifneq ($(KBUILD_OUTPUT),)
179
180ifeq ($(abs_objtree),$(CURDIR))
181# Suppress "Entering directory ..." unless we are changing the work directory.
182MAKEFLAGS += --no-print-directory
183else
184need-sub-make := 1
185endif
186
187this-makefile := $(lastword $(MAKEFILE_LIST))
188abs_srctree := $(realpath $(dir $(this-makefile)))
189
190ifneq ($(words $(subst :, ,$(abs_srctree))), 1)
191$(error source directory cannot contain spaces or colons)
192endif
193
194ifneq ($(abs_srctree),$(abs_objtree))
195# Look for make include files relative to root of kernel src
196#
197# --included-dir is added for backward compatibility, but you should not rely on
198# it. Please add $(srctree)/ prefix to include Makefiles in the source tree.
199MAKEFLAGS += --include-dir=$(abs_srctree)
200endif
201
202ifneq ($(filter 3.%,$(MAKE_VERSION)),)
203# 'MAKEFLAGS += -rR' does not immediately become effective for GNU Make 3.x
204# We need to invoke sub-make to avoid implicit rules in the top Makefile.
205need-sub-make := 1
206# Cancel implicit rules for this Makefile.
207$(this-makefile): ;
208endif
209
210export abs_srctree abs_objtree
211export sub_make_done := 1
212
213ifeq ($(need-sub-make),1)
214
215PHONY += $(MAKECMDGOALS) __sub-make
216
217$(filter-out $(this-makefile), $(MAKECMDGOALS)) __all: __sub-make
218	@:
219
220# Invoke a second make in the output directory, passing relevant variables
221__sub-make:
222	$(Q)$(MAKE) -C $(abs_objtree) -f $(abs_srctree)/Makefile $(MAKECMDGOALS)
223
224endif # need-sub-make
225endif # sub_make_done
226
227# We process the rest of the Makefile if this is the final invocation of make
228ifeq ($(need-sub-make),)
229
230# Do not print "Entering directory ...",
231# but we want to display it when entering to the output directory
232# so that IDEs/editors are able to understand relative filenames.
233MAKEFLAGS += --no-print-directory
234
235ifeq ($(abs_srctree),$(abs_objtree))
236        # building in the source tree
237        srctree := .
238	building_out_of_srctree :=
239else
240        ifeq ($(abs_srctree)/,$(dir $(abs_objtree)))
241                # building in a subdirectory of the source tree
242                srctree := ..
243        else
244                srctree := $(abs_srctree)
245        endif
246	building_out_of_srctree := 1
247endif
248
249ifneq ($(KBUILD_ABS_SRCTREE),)
250srctree := $(abs_srctree)
251endif
252
253objtree		:= .
254VPATH		:= $(srctree)
255
256export building_out_of_srctree srctree objtree VPATH
257
258# To make sure we do not include .config for any of the *config targets
259# catch them early, and hand them over to scripts/kconfig/Makefile
260# It is allowed to specify more targets when calling make, including
261# mixing *config targets and build targets.
262# For example 'make oldconfig all'.
263# Detect when mixed targets is specified, and make a second invocation
264# of make so .config is not included in this case either (for *config).
265
266version_h := include/generated/uapi/linux/version.h
267
268clean-targets := %clean mrproper cleandocs
269no-dot-config-targets := $(clean-targets) \
270			 cscope gtags TAGS tags help% %docs check% coccicheck \
271			 $(version_h) headers headers_% archheaders archscripts \
272			 %asm-generic kernelversion %src-pkg dt_binding_check \
273			 outputmakefile
274# Installation targets should not require compiler. Unfortunately, vdso_install
275# is an exception where build artifacts may be updated. This must be fixed.
276no-compiler-targets := $(no-dot-config-targets) install dtbs_install \
277			headers_install modules_install kernelrelease image_name
278no-sync-config-targets := $(no-dot-config-targets) %install kernelrelease \
279			  image_name
280single-targets := %.a %.i %.ko %.lds %.ll %.lst %.mod %.o %.s %.symtypes %/
281
282config-build	:=
283mixed-build	:=
284need-config	:= 1
285need-compiler	:= 1
286may-sync-config	:= 1
287single-build	:=
288
289ifneq ($(filter $(no-dot-config-targets), $(MAKECMDGOALS)),)
290	ifeq ($(filter-out $(no-dot-config-targets), $(MAKECMDGOALS)),)
291		need-config :=
292	endif
293endif
294
295ifneq ($(filter $(no-compiler-targets), $(MAKECMDGOALS)),)
296	ifeq ($(filter-out $(no-compiler-targets), $(MAKECMDGOALS)),)
297		need-compiler :=
298	endif
299endif
300
301ifneq ($(filter $(no-sync-config-targets), $(MAKECMDGOALS)),)
302	ifeq ($(filter-out $(no-sync-config-targets), $(MAKECMDGOALS)),)
303		may-sync-config :=
304	endif
305endif
306
307ifneq ($(KBUILD_EXTMOD),)
308	may-sync-config :=
309endif
310
311ifeq ($(KBUILD_EXTMOD),)
312        ifneq ($(filter %config,$(MAKECMDGOALS)),)
313		config-build := 1
314                ifneq ($(words $(MAKECMDGOALS)),1)
315			mixed-build := 1
316                endif
317        endif
318endif
319
320# We cannot build single targets and the others at the same time
321ifneq ($(filter $(single-targets), $(MAKECMDGOALS)),)
322	single-build := 1
323	ifneq ($(filter-out $(single-targets), $(MAKECMDGOALS)),)
324		mixed-build := 1
325	endif
326endif
327
328# For "make -j clean all", "make -j mrproper defconfig all", etc.
329ifneq ($(filter $(clean-targets),$(MAKECMDGOALS)),)
330        ifneq ($(filter-out $(clean-targets),$(MAKECMDGOALS)),)
331		mixed-build := 1
332        endif
333endif
334
335# install and modules_install need also be processed one by one
336ifneq ($(filter install,$(MAKECMDGOALS)),)
337        ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
338		mixed-build := 1
339        endif
340endif
341
342ifdef mixed-build
343# ===========================================================================
344# We're called with mixed targets (*config and build targets).
345# Handle them one by one.
346
347PHONY += $(MAKECMDGOALS) __build_one_by_one
348
349$(MAKECMDGOALS): __build_one_by_one
350	@:
351
352__build_one_by_one:
353	$(Q)set -e; \
354	for i in $(MAKECMDGOALS); do \
355		$(MAKE) -f $(srctree)/Makefile $$i; \
356	done
357
358else # !mixed-build
359
360include $(srctree)/scripts/Kbuild.include
361
362# Read KERNELRELEASE from include/config/kernel.release (if it exists)
363KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null)
364KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION)
365export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
366
367include $(srctree)/scripts/subarch.include
368
369# Cross compiling and selecting different set of gcc/bin-utils
370# ---------------------------------------------------------------------------
371#
372# When performing cross compilation for other architectures ARCH shall be set
373# to the target architecture. (See arch/* for the possibilities).
374# ARCH can be set during invocation of make:
375# make ARCH=ia64
376# Another way is to have ARCH set in the environment.
377# The default ARCH is the host where make is executed.
378
379# CROSS_COMPILE specify the prefix used for all executables used
380# during compilation. Only gcc and related bin-utils executables
381# are prefixed with $(CROSS_COMPILE).
382# CROSS_COMPILE can be set on the command line
383# make CROSS_COMPILE=ia64-linux-
384# Alternatively CROSS_COMPILE can be set in the environment.
385# Default value for CROSS_COMPILE is not to prefix executables
386# Note: Some architectures assign CROSS_COMPILE in their arch/*/Makefile
387ARCH		?= $(SUBARCH)
388
389# Architecture as present in compile.h
390UTS_MACHINE 	:= $(ARCH)
391SRCARCH 	:= $(ARCH)
392
393# Additional ARCH settings for x86
394ifeq ($(ARCH),i386)
395        SRCARCH := x86
396endif
397ifeq ($(ARCH),x86_64)
398        SRCARCH := x86
399endif
400
401# Additional ARCH settings for sparc
402ifeq ($(ARCH),sparc32)
403       SRCARCH := sparc
404endif
405ifeq ($(ARCH),sparc64)
406       SRCARCH := sparc
407endif
408
409# Additional ARCH settings for parisc
410ifeq ($(ARCH),parisc64)
411       SRCARCH := parisc
412endif
413
414export cross_compiling :=
415ifneq ($(SRCARCH),$(SUBARCH))
416cross_compiling := 1
417endif
418
419KCONFIG_CONFIG	?= .config
420export KCONFIG_CONFIG
421
422# SHELL used by kbuild
423CONFIG_SHELL := sh
424
425HOST_LFS_CFLAGS := $(shell getconf LFS_CFLAGS 2>/dev/null)
426HOST_LFS_LDFLAGS := $(shell getconf LFS_LDFLAGS 2>/dev/null)
427HOST_LFS_LIBS := $(shell getconf LFS_LIBS 2>/dev/null)
428
429ifneq ($(LLVM),)
430ifneq ($(filter %/,$(LLVM)),)
431LLVM_PREFIX := $(LLVM)
432else ifneq ($(filter -%,$(LLVM)),)
433LLVM_SUFFIX := $(LLVM)
434endif
435
436HOSTCC	= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
437HOSTCXX	= $(LLVM_PREFIX)clang++$(LLVM_SUFFIX)
438else
439HOSTCC	= gcc
440HOSTCXX	= g++
441endif
442HOSTPKG_CONFIG	= pkg-config
443
444KBUILD_USERHOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes \
445			 -O2 -fomit-frame-pointer -std=gnu11 \
446			 -Wdeclaration-after-statement
447KBUILD_USERCFLAGS  := $(KBUILD_USERHOSTCFLAGS) $(USERCFLAGS)
448KBUILD_USERLDFLAGS := $(USERLDFLAGS)
449
450KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) $(HOSTCFLAGS)
451KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
452KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
453KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
454
455# Make variables (CC, etc...)
456CPP		= $(CC) -E
457ifneq ($(LLVM),)
458CC		= $(LLVM_PREFIX)clang$(LLVM_SUFFIX)
459LD		= $(LLVM_PREFIX)ld.lld$(LLVM_SUFFIX)
460AR		= $(LLVM_PREFIX)llvm-ar$(LLVM_SUFFIX)
461NM		= $(LLVM_PREFIX)llvm-nm$(LLVM_SUFFIX)
462OBJCOPY		= $(LLVM_PREFIX)llvm-objcopy$(LLVM_SUFFIX)
463OBJDUMP		= $(LLVM_PREFIX)llvm-objdump$(LLVM_SUFFIX)
464READELF		= $(LLVM_PREFIX)llvm-readelf$(LLVM_SUFFIX)
465STRIP		= $(LLVM_PREFIX)llvm-strip$(LLVM_SUFFIX)
466else
467CC		= $(CROSS_COMPILE)gcc
468LD		= $(CROSS_COMPILE)ld
469AR		= $(CROSS_COMPILE)ar
470NM		= $(CROSS_COMPILE)nm
471OBJCOPY		= $(CROSS_COMPILE)objcopy
472OBJDUMP		= $(CROSS_COMPILE)objdump
473READELF		= $(CROSS_COMPILE)readelf
474STRIP		= $(CROSS_COMPILE)strip
475endif
476PAHOLE		= pahole
477RESOLVE_BTFIDS	= $(objtree)/tools/bpf/resolve_btfids/resolve_btfids
478LEX		= flex
479YACC		= bison
480AWK		= awk
481INSTALLKERNEL  := installkernel
482DEPMOD		= depmod
483PERL		= perl
484PYTHON3		= python3
485CHECK		= sparse
486BASH		= bash
487KGZIP		= gzip
488KBZIP2		= bzip2
489KLZOP		= lzop
490LZMA		= lzma
491LZ4		= lz4c
492XZ		= xz
493ZSTD		= zstd
494
495PAHOLE_FLAGS	= $(shell PAHOLE=$(PAHOLE) $(srctree)/scripts/pahole-flags.sh)
496
497CHECKFLAGS     := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
498		  -Wbitwise -Wno-return-void -Wno-unknown-attribute $(CF)
499NOSTDINC_FLAGS :=
500CFLAGS_MODULE   =
501AFLAGS_MODULE   =
502LDFLAGS_MODULE  =
503CFLAGS_KERNEL	=
504AFLAGS_KERNEL	=
505LDFLAGS_vmlinux =
506
507# Use USERINCLUDE when you must reference the UAPI directories only.
508USERINCLUDE    := \
509		-I$(srctree)/arch/$(SRCARCH)/include/uapi \
510		-I$(objtree)/arch/$(SRCARCH)/include/generated/uapi \
511		-I$(srctree)/include/uapi \
512		-I$(objtree)/include/generated/uapi \
513                -include $(srctree)/include/linux/compiler-version.h \
514                -include $(srctree)/include/linux/kconfig.h
515
516# Use LINUXINCLUDE when you must reference the include/ directory.
517# Needed to be compatible with the O= option
518LINUXINCLUDE    := \
519		-I$(srctree)/arch/$(SRCARCH)/include \
520		-I$(objtree)/arch/$(SRCARCH)/include/generated \
521		$(if $(building_out_of_srctree),-I$(srctree)/include) \
522		-I$(objtree)/include \
523		$(USERINCLUDE)
524
525KBUILD_AFLAGS   := -D__ASSEMBLY__ -fno-PIE
526KBUILD_CFLAGS   := -Wall -Wundef -Werror=strict-prototypes -Wno-trigraphs \
527		   -fno-strict-aliasing -fno-common -fshort-wchar -fno-PIE \
528		   -Werror=implicit-function-declaration -Werror=implicit-int \
529		   -Werror=return-type -Wno-format-security \
530		   -std=gnu11
531KBUILD_CPPFLAGS := -D__KERNEL__
532KBUILD_AFLAGS_KERNEL :=
533KBUILD_CFLAGS_KERNEL :=
534KBUILD_AFLAGS_MODULE  := -DMODULE
535KBUILD_CFLAGS_MODULE  := -DMODULE
536KBUILD_LDFLAGS_MODULE :=
537KBUILD_LDFLAGS :=
538CLANG_FLAGS :=
539
540export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC HOSTPKG_CONFIG
541export CPP AR NM STRIP OBJCOPY OBJDUMP READELF PAHOLE RESOLVE_BTFIDS LEX YACC AWK INSTALLKERNEL
542export PERL PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
543export KGZIP KBZIP2 KLZOP LZMA LZ4 XZ ZSTD
544export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
545export KBUILD_USERCFLAGS KBUILD_USERLDFLAGS
546
547export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS KBUILD_LDFLAGS
548export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
549export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
550export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
551export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
552export PAHOLE_FLAGS
553
554# Files to ignore in find ... statements
555
556export RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o    \
557			  -name CVS -o -name .pc -o -name .hg -o -name .git \) \
558			  -prune -o
559export RCS_TAR_IGNORE := --exclude SCCS --exclude BitKeeper --exclude .svn \
560			 --exclude CVS --exclude .pc --exclude .hg --exclude .git
561
562# ===========================================================================
563# Rules shared between *config targets and build targets
564
565# Basic helpers built in scripts/basic/
566PHONY += scripts_basic
567scripts_basic:
568	$(Q)$(MAKE) $(build)=scripts/basic
569
570PHONY += outputmakefile
571ifdef building_out_of_srctree
572# Before starting out-of-tree build, make sure the source tree is clean.
573# outputmakefile generates a Makefile in the output directory, if using a
574# separate output directory. This allows convenient use of make in the
575# output directory.
576# At the same time when output Makefile generated, generate .gitignore to
577# ignore whole output directory
578
579quiet_cmd_makefile = GEN     Makefile
580      cmd_makefile = { \
581	echo "\# Automatically generated by $(srctree)/Makefile: don't edit"; \
582	echo "include $(srctree)/Makefile"; \
583	} > Makefile
584
585outputmakefile:
586	$(Q)if [ -f $(srctree)/.config -o \
587		 -d $(srctree)/include/config -o \
588		 -d $(srctree)/arch/$(SRCARCH)/include/generated ]; then \
589		echo >&2 "***"; \
590		echo >&2 "*** The source tree is not clean, please run 'make$(if $(findstring command line, $(origin ARCH)), ARCH=$(ARCH)) mrproper'"; \
591		echo >&2 "*** in $(abs_srctree)";\
592		echo >&2 "***"; \
593		false; \
594	fi
595	$(Q)ln -fsn $(srctree) source
596	$(call cmd,makefile)
597	$(Q)test -e .gitignore || \
598	{ echo "# this is build directory, ignore it"; echo "*"; } > .gitignore
599endif
600
601# The expansion should be delayed until arch/$(SRCARCH)/Makefile is included.
602# Some architectures define CROSS_COMPILE in arch/$(SRCARCH)/Makefile.
603# CC_VERSION_TEXT is referenced from Kconfig (so it needs export),
604# and from include/config/auto.conf.cmd to detect the compiler upgrade.
605CC_VERSION_TEXT = $(subst $(pound),,$(shell LC_ALL=C $(CC) --version 2>/dev/null | head -n 1))
606
607ifneq ($(findstring clang,$(CC_VERSION_TEXT)),)
608include $(srctree)/scripts/Makefile.clang
609endif
610
611# Include this also for config targets because some architectures need
612# cc-cross-prefix to determine CROSS_COMPILE.
613ifdef need-compiler
614include $(srctree)/scripts/Makefile.compiler
615endif
616
617ifdef config-build
618# ===========================================================================
619# *config targets only - make sure prerequisites are updated, and descend
620# in scripts/kconfig to make the *config target
621
622# Read arch specific Makefile to set KBUILD_DEFCONFIG as needed.
623# KBUILD_DEFCONFIG may point out an alternative default configuration
624# used for 'make defconfig'
625include $(srctree)/arch/$(SRCARCH)/Makefile
626export KBUILD_DEFCONFIG KBUILD_KCONFIG CC_VERSION_TEXT
627
628config: outputmakefile scripts_basic FORCE
629	$(Q)$(MAKE) $(build)=scripts/kconfig $@
630
631%config: outputmakefile scripts_basic FORCE
632	$(Q)$(MAKE) $(build)=scripts/kconfig $@
633
634else #!config-build
635# ===========================================================================
636# Build targets only - this includes vmlinux, arch specific targets, clean
637# targets and others. In general all targets except *config targets.
638
639# If building an external module we do not care about the all: rule
640# but instead __all depend on modules
641PHONY += all
642ifeq ($(KBUILD_EXTMOD),)
643__all: all
644else
645__all: modules
646endif
647
648# Decide whether to build built-in, modular, or both.
649# Normally, just do built-in.
650
651KBUILD_MODULES :=
652KBUILD_BUILTIN := 1
653
654# If we have only "make modules", don't compile built-in objects.
655ifeq ($(MAKECMDGOALS),modules)
656  KBUILD_BUILTIN :=
657endif
658
659# If we have "make <whatever> modules", compile modules
660# in addition to whatever we do anyway.
661# Just "make" or "make all" shall build modules as well
662
663ifneq ($(filter all modules nsdeps %compile_commands.json clang-%,$(MAKECMDGOALS)),)
664  KBUILD_MODULES := 1
665endif
666
667ifeq ($(MAKECMDGOALS),)
668  KBUILD_MODULES := 1
669endif
670
671export KBUILD_MODULES KBUILD_BUILTIN
672
673ifdef need-config
674include include/config/auto.conf
675endif
676
677ifeq ($(KBUILD_EXTMOD),)
678# Objects we will link into vmlinux / subdirs we need to visit
679core-y		:= init/ usr/ arch/$(SRCARCH)/
680drivers-y	:= drivers/ sound/
681drivers-$(CONFIG_SAMPLES) += samples/
682drivers-$(CONFIG_NET) += net/
683drivers-y	+= virt/
684libs-y		:= lib/
685endif # KBUILD_EXTMOD
686
687# The all: target is the default when no target is given on the
688# command line.
689# This allow a user to issue only 'make' to build a kernel including modules
690# Defaults to vmlinux, but the arch makefile usually adds further targets
691all: vmlinux
692
693CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage
694ifdef CONFIG_CC_IS_GCC
695CFLAGS_GCOV	+= -fno-tree-loop-im
696endif
697export CFLAGS_GCOV
698
699# The arch Makefiles can override CC_FLAGS_FTRACE. We may also append it later.
700ifdef CONFIG_FUNCTION_TRACER
701  CC_FLAGS_FTRACE := -pg
702endif
703
704include $(srctree)/arch/$(SRCARCH)/Makefile
705
706ifdef need-config
707ifdef may-sync-config
708# Read in dependencies to all Kconfig* files, make sure to run syncconfig if
709# changes are detected. This should be included after arch/$(SRCARCH)/Makefile
710# because some architectures define CROSS_COMPILE there.
711include include/config/auto.conf.cmd
712
713$(KCONFIG_CONFIG):
714	@echo >&2 '***'
715	@echo >&2 '*** Configuration file "$@" not found!'
716	@echo >&2 '***'
717	@echo >&2 '*** Please run some configurator (e.g. "make oldconfig" or'
718	@echo >&2 '*** "make menuconfig" or "make xconfig").'
719	@echo >&2 '***'
720	@/bin/false
721
722# The actual configuration files used during the build are stored in
723# include/generated/ and include/config/. Update them if .config is newer than
724# include/config/auto.conf (which mirrors .config).
725#
726# This exploits the 'multi-target pattern rule' trick.
727# The syncconfig should be executed only once to make all the targets.
728# (Note: use the grouped target '&:' when we bump to GNU Make 4.3)
729#
730# Do not use $(call cmd,...) here. That would suppress prompts from syncconfig,
731# so you cannot notice that Kconfig is waiting for the user input.
732%/config/auto.conf %/config/auto.conf.cmd %/generated/autoconf.h: $(KCONFIG_CONFIG)
733	$(Q)$(kecho) "  SYNC    $@"
734	$(Q)$(MAKE) -f $(srctree)/Makefile syncconfig
735else # !may-sync-config
736# External modules and some install targets need include/generated/autoconf.h
737# and include/config/auto.conf but do not care if they are up-to-date.
738# Use auto.conf to trigger the test
739PHONY += include/config/auto.conf
740
741include/config/auto.conf:
742	$(Q)test -e include/generated/autoconf.h -a -e $@ || (		\
743	echo >&2;							\
744	echo >&2 "  ERROR: Kernel configuration is invalid.";		\
745	echo >&2 "         include/generated/autoconf.h or $@ are missing.";\
746	echo >&2 "         Run 'make oldconfig && make prepare' on kernel src to fix it.";	\
747	echo >&2 ;							\
748	/bin/false)
749
750endif # may-sync-config
751endif # need-config
752
753KBUILD_CFLAGS	+= -fno-delete-null-pointer-checks
754KBUILD_CFLAGS	+= $(call cc-disable-warning,frame-address,)
755KBUILD_CFLAGS	+= $(call cc-disable-warning, format-truncation)
756KBUILD_CFLAGS	+= $(call cc-disable-warning, format-overflow)
757KBUILD_CFLAGS	+= $(call cc-disable-warning, address-of-packed-member)
758
759ifdef CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE
760KBUILD_CFLAGS += -O2
761else ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
762KBUILD_CFLAGS += -Os
763endif
764
765# Tell gcc to never replace conditional load with a non-conditional one
766ifdef CONFIG_CC_IS_GCC
767# gcc-10 renamed --param=allow-store-data-races=0 to
768# -fno-allow-store-data-races.
769KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
770KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
771endif
772
773ifdef CONFIG_READABLE_ASM
774# Disable optimizations that make assembler listings hard to read.
775# reorder blocks reorders the control in the function
776# ipa clone creates specialized cloned functions
777# partial inlining inlines only parts of functions
778KBUILD_CFLAGS += -fno-reorder-blocks -fno-ipa-cp-clone -fno-partial-inlining
779endif
780
781ifneq ($(CONFIG_FRAME_WARN),0)
782KBUILD_CFLAGS += -Wframe-larger-than=$(CONFIG_FRAME_WARN)
783endif
784
785stackp-flags-y                                    := -fno-stack-protector
786stackp-flags-$(CONFIG_STACKPROTECTOR)             := -fstack-protector
787stackp-flags-$(CONFIG_STACKPROTECTOR_STRONG)      := -fstack-protector-strong
788
789KBUILD_CFLAGS += $(stackp-flags-y)
790
791KBUILD_CFLAGS-$(CONFIG_WERROR) += -Werror
792KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds
793KBUILD_CFLAGS += $(KBUILD_CFLAGS-y) $(CONFIG_CC_IMPLICIT_FALLTHROUGH)
794
795ifdef CONFIG_CC_IS_CLANG
796KBUILD_CPPFLAGS += -Qunused-arguments
797# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.
798KBUILD_CFLAGS += -Wno-gnu
799else
800
801# gcc inanely warns about local variables called 'main'
802KBUILD_CFLAGS += -Wno-main
803endif
804
805# These warnings generated too much noise in a regular build.
806# Use make W=1 to enable them (see scripts/Makefile.extrawarn)
807KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
808KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
809
810# These result in bogus false positives
811KBUILD_CFLAGS += $(call cc-disable-warning, dangling-pointer)
812
813ifdef CONFIG_FRAME_POINTER
814KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
815else
816# Some targets (ARM with Thumb2, for example), can't be built with frame
817# pointers.  For those, we don't have FUNCTION_TRACER automatically
818# select FRAME_POINTER.  However, FUNCTION_TRACER adds -pg, and this is
819# incompatible with -fomit-frame-pointer with current GCC, so we don't use
820# -fomit-frame-pointer with FUNCTION_TRACER.
821ifndef CONFIG_FUNCTION_TRACER
822KBUILD_CFLAGS	+= -fomit-frame-pointer
823endif
824endif
825
826# Initialize all stack variables with a 0xAA pattern.
827ifdef CONFIG_INIT_STACK_ALL_PATTERN
828KBUILD_CFLAGS	+= -ftrivial-auto-var-init=pattern
829endif
830
831# Initialize all stack variables with a zero value.
832ifdef CONFIG_INIT_STACK_ALL_ZERO
833KBUILD_CFLAGS	+= -ftrivial-auto-var-init=zero
834ifdef CONFIG_CC_IS_CLANG
835# https://bugs.llvm.org/show_bug.cgi?id=45497
836KBUILD_CFLAGS	+= -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
837endif
838endif
839
840# While VLAs have been removed, GCC produces unreachable stack probes
841# for the randomize_kstack_offset feature. Disable it for all compilers.
842KBUILD_CFLAGS	+= $(call cc-option, -fno-stack-clash-protection)
843
844# Clear used registers at func exit (to reduce data lifetime and ROP gadgets).
845ifdef CONFIG_ZERO_CALL_USED_REGS
846KBUILD_CFLAGS	+= -fzero-call-used-regs=used-gpr
847endif
848
849ifdef CONFIG_FUNCTION_TRACER
850ifdef CONFIG_FTRACE_MCOUNT_USE_CC
851  CC_FLAGS_FTRACE	+= -mrecord-mcount
852  ifdef CONFIG_HAVE_NOP_MCOUNT
853    ifeq ($(call cc-option-yn, -mnop-mcount),y)
854      CC_FLAGS_FTRACE	+= -mnop-mcount
855      CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
856    endif
857  endif
858endif
859ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
860  CC_FLAGS_USING	+= -DCC_USING_NOP_MCOUNT
861endif
862ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT
863  ifdef CONFIG_HAVE_C_RECORDMCOUNT
864    BUILD_C_RECORDMCOUNT := y
865    export BUILD_C_RECORDMCOUNT
866  endif
867endif
868ifdef CONFIG_HAVE_FENTRY
869  # s390-linux-gnu-gcc did not support -mfentry until gcc-9.
870  ifeq ($(call cc-option-yn, -mfentry),y)
871    CC_FLAGS_FTRACE	+= -mfentry
872    CC_FLAGS_USING	+= -DCC_USING_FENTRY
873  endif
874endif
875export CC_FLAGS_FTRACE
876KBUILD_CFLAGS	+= $(CC_FLAGS_FTRACE) $(CC_FLAGS_USING)
877KBUILD_AFLAGS	+= $(CC_FLAGS_USING)
878endif
879
880# We trigger additional mismatches with less inlining
881ifdef CONFIG_DEBUG_SECTION_MISMATCH
882KBUILD_CFLAGS += -fno-inline-functions-called-once
883endif
884
885ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
886KBUILD_CFLAGS_KERNEL += -ffunction-sections -fdata-sections
887LDFLAGS_vmlinux += --gc-sections
888endif
889
890ifdef CONFIG_SHADOW_CALL_STACK
891CC_FLAGS_SCS	:= -fsanitize=shadow-call-stack
892KBUILD_CFLAGS	+= $(CC_FLAGS_SCS)
893export CC_FLAGS_SCS
894endif
895
896ifdef CONFIG_LTO_CLANG
897ifdef CONFIG_LTO_CLANG_THIN
898CC_FLAGS_LTO	:= -flto=thin -fsplit-lto-unit
899KBUILD_LDFLAGS	+= --thinlto-cache-dir=$(extmod_prefix).thinlto-cache
900else
901CC_FLAGS_LTO	:= -flto
902endif
903CC_FLAGS_LTO	+= -fvisibility=hidden
904
905# Limit inlining across translation units to reduce binary size
906KBUILD_LDFLAGS += -mllvm -import-instr-limit=5
907
908# Check for frame size exceeding threshold during prolog/epilog insertion
909# when using lld < 13.0.0.
910ifneq ($(CONFIG_FRAME_WARN),0)
911ifeq ($(shell test $(CONFIG_LLD_VERSION) -lt 130000; echo $$?),0)
912KBUILD_LDFLAGS	+= -plugin-opt=-warn-stack-size=$(CONFIG_FRAME_WARN)
913endif
914endif
915endif
916
917ifdef CONFIG_LTO
918KBUILD_CFLAGS	+= -fno-lto $(CC_FLAGS_LTO)
919KBUILD_AFLAGS	+= -fno-lto
920export CC_FLAGS_LTO
921endif
922
923ifdef CONFIG_CFI_CLANG
924CC_FLAGS_CFI	:= -fsanitize=cfi \
925		   -fsanitize-cfi-cross-dso \
926		   -fno-sanitize-cfi-canonical-jump-tables \
927		   -fno-sanitize-trap=cfi \
928		   -fno-sanitize-blacklist
929
930ifdef CONFIG_CFI_PERMISSIVE
931CC_FLAGS_CFI	+= -fsanitize-recover=cfi
932endif
933
934# If LTO flags are filtered out, we must also filter out CFI.
935CC_FLAGS_LTO	+= $(CC_FLAGS_CFI)
936KBUILD_CFLAGS	+= $(CC_FLAGS_CFI)
937export CC_FLAGS_CFI
938endif
939
940ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_64B
941KBUILD_CFLAGS += -falign-functions=64
942endif
943
944# arch Makefile may override CC so keep this after arch Makefile is included
945NOSTDINC_FLAGS += -nostdinc
946
947# warn about C99 declaration after statement
948KBUILD_CFLAGS += -Wdeclaration-after-statement
949
950# Variable Length Arrays (VLAs) should not be used anywhere in the kernel
951KBUILD_CFLAGS += -Wvla
952
953# disable pointer signed / unsigned warnings in gcc 4.0
954KBUILD_CFLAGS += -Wno-pointer-sign
955
956# In order to make sure new function cast mismatches are not introduced
957# in the kernel (to avoid tripping CFI checking), the kernel should be
958# globally built with -Wcast-function-type.
959KBUILD_CFLAGS += $(call cc-option, -Wcast-function-type)
960
961# disable stringop warnings in gcc 8+
962KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
963
964# We'll want to enable this eventually, but it's not going away for 5.7 at least
965KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
966
967# Another good warning that we'll want to enable eventually
968KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
969
970# Enabled with W=2, disabled by default as noisy
971ifdef CONFIG_CC_IS_GCC
972KBUILD_CFLAGS += -Wno-maybe-uninitialized
973endif
974
975ifdef CONFIG_CC_IS_GCC
976# The allocators already balk at large sizes, so silence the compiler
977# warnings for bounds checks involving those possible values. While
978# -Wno-alloc-size-larger-than would normally be used here, earlier versions
979# of gcc (<9.1) weirdly don't handle the option correctly when _other_
980# warnings are produced (?!). Using -Walloc-size-larger-than=SIZE_MAX
981# doesn't work (as it is documented to), silently resolving to "0" prior to
982# version 9.1 (and producing an error more recently). Numeric values larger
983# than PTRDIFF_MAX also don't work prior to version 9.1, which are silently
984# ignored, continuing to default to PTRDIFF_MAX. So, left with no other
985# choice, we must perform a versioned check to disable this warning.
986# https://lore.kernel.org/lkml/20210824115859.187f272f@canb.auug.org.au
987KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than)
988endif
989
990# disable invalid "can't wrap" optimizations for signed / pointers
991KBUILD_CFLAGS	+= -fno-strict-overflow
992
993# Make sure -fstack-check isn't enabled (like gentoo apparently did)
994KBUILD_CFLAGS  += -fno-stack-check
995
996# conserve stack if available
997ifdef CONFIG_CC_IS_GCC
998KBUILD_CFLAGS   += -fconserve-stack
999endif
1000
1001# Prohibit date/time macros, which would make the build non-deterministic
1002KBUILD_CFLAGS   += -Werror=date-time
1003
1004# enforce correct pointer usage
1005KBUILD_CFLAGS   += $(call cc-option,-Werror=incompatible-pointer-types)
1006
1007# Require designated initializers for all marked structures
1008KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
1009
1010# change __FILE__ to the relative path from the srctree
1011KBUILD_CPPFLAGS += $(call cc-option,-fmacro-prefix-map=$(srctree)/=)
1012
1013# include additional Makefiles when needed
1014include-y			:= scripts/Makefile.extrawarn
1015include-$(CONFIG_DEBUG_INFO)	+= scripts/Makefile.debug
1016include-$(CONFIG_KASAN)		+= scripts/Makefile.kasan
1017include-$(CONFIG_KCSAN)		+= scripts/Makefile.kcsan
1018include-$(CONFIG_UBSAN)		+= scripts/Makefile.ubsan
1019include-$(CONFIG_KCOV)		+= scripts/Makefile.kcov
1020include-$(CONFIG_RANDSTRUCT)	+= scripts/Makefile.randstruct
1021include-$(CONFIG_GCC_PLUGINS)	+= scripts/Makefile.gcc-plugins
1022
1023include $(addprefix $(srctree)/, $(include-y))
1024
1025# scripts/Makefile.gcc-plugins is intentionally included last.
1026# Do not add $(call cc-option,...) below this line. When you build the kernel
1027# from the clean source tree, the GCC plugins do not exist at this point.
1028
1029# Add user supplied CPPFLAGS, AFLAGS and CFLAGS as the last assignments
1030KBUILD_CPPFLAGS += $(KCPPFLAGS)
1031KBUILD_AFLAGS   += $(KAFLAGS)
1032KBUILD_CFLAGS   += $(KCFLAGS)
1033
1034KBUILD_LDFLAGS_MODULE += --build-id=sha1
1035LDFLAGS_vmlinux += --build-id=sha1
1036
1037KBUILD_LDFLAGS	+= -z noexecstack
1038ifeq ($(CONFIG_LD_IS_BFD),y)
1039KBUILD_LDFLAGS	+= $(call ld-option,--no-warn-rwx-segments)
1040endif
1041
1042ifeq ($(CONFIG_STRIP_ASM_SYMS),y)
1043LDFLAGS_vmlinux	+= $(call ld-option, -X,)
1044endif
1045
1046ifeq ($(CONFIG_RELR),y)
1047LDFLAGS_vmlinux	+= --pack-dyn-relocs=relr --use-android-relr-tags
1048endif
1049
1050# We never want expected sections to be placed heuristically by the
1051# linker. All sections should be explicitly named in the linker script.
1052ifdef CONFIG_LD_ORPHAN_WARN
1053LDFLAGS_vmlinux += --orphan-handling=warn
1054endif
1055
1056# Align the bit size of userspace programs with the kernel
1057KBUILD_USERCFLAGS  += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1058KBUILD_USERLDFLAGS += $(filter -m32 -m64 --target=%, $(KBUILD_CFLAGS))
1059
1060# make the checker run with the right architecture
1061CHECKFLAGS += --arch=$(ARCH)
1062
1063# insure the checker run with the right endianness
1064CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian)
1065
1066# the checker needs the correct machine size
1067CHECKFLAGS += $(if $(CONFIG_64BIT),-m64,-m32)
1068
1069# Default kernel image to build when no specific target is given.
1070# KBUILD_IMAGE may be overruled on the command line or
1071# set in the environment
1072# Also any assignments in arch/$(ARCH)/Makefile take precedence over
1073# this default value
1074export KBUILD_IMAGE ?= vmlinux
1075
1076#
1077# INSTALL_PATH specifies where to place the updated kernel and system map
1078# images. Default is /boot, but you can set it to other values
1079export	INSTALL_PATH ?= /boot
1080
1081#
1082# INSTALL_DTBS_PATH specifies a prefix for relocations required by build roots.
1083# Like INSTALL_MOD_PATH, it isn't defined in the Makefile, but can be passed as
1084# an argument if needed. Otherwise it defaults to the kernel install path
1085#
1086export INSTALL_DTBS_PATH ?= $(INSTALL_PATH)/dtbs/$(KERNELRELEASE)
1087
1088#
1089# INSTALL_MOD_PATH specifies a prefix to MODLIB for module directory
1090# relocations required by build roots.  This is not defined in the
1091# makefile but the argument can be passed to make if needed.
1092#
1093
1094MODLIB	= $(INSTALL_MOD_PATH)/lib/modules/$(KERNELRELEASE)
1095export MODLIB
1096
1097PHONY += prepare0
1098
1099export extmod_prefix = $(if $(KBUILD_EXTMOD),$(KBUILD_EXTMOD)/)
1100export MODORDER := $(extmod_prefix)modules.order
1101export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
1102
1103ifeq ($(KBUILD_EXTMOD),)
1104core-y			+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/
1105core-$(CONFIG_BLOCK)	+= block/
1106core-$(CONFIG_IO_URING)	+= io_uring/
1107
1108vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
1109		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
1110		     $(libs-y) $(libs-m)))
1111
1112vmlinux-alldirs	:= $(sort $(vmlinux-dirs) Documentation \
1113		     $(patsubst %/,%,$(filter %/, $(core-) \
1114			$(drivers-) $(libs-))))
1115
1116subdir-modorder := $(addsuffix modules.order,$(filter %/, \
1117			$(core-y) $(core-m) $(libs-y) $(libs-m) \
1118			$(drivers-y) $(drivers-m)))
1119
1120build-dirs	:= $(vmlinux-dirs)
1121clean-dirs	:= $(vmlinux-alldirs)
1122
1123# Externally visible symbols (used by link-vmlinux.sh)
1124KBUILD_VMLINUX_OBJS := $(head-y) $(patsubst %/,%/built-in.a, $(core-y))
1125KBUILD_VMLINUX_OBJS += $(addsuffix built-in.a, $(filter %/, $(libs-y)))
1126ifdef CONFIG_MODULES
1127KBUILD_VMLINUX_OBJS += $(patsubst %/, %/lib.a, $(filter %/, $(libs-y)))
1128KBUILD_VMLINUX_LIBS := $(filter-out %/, $(libs-y))
1129else
1130KBUILD_VMLINUX_LIBS := $(patsubst %/,%/lib.a, $(libs-y))
1131endif
1132KBUILD_VMLINUX_OBJS += $(patsubst %/,%/built-in.a, $(drivers-y))
1133
1134export KBUILD_VMLINUX_OBJS KBUILD_VMLINUX_LIBS
1135export KBUILD_LDS          := arch/$(SRCARCH)/kernel/vmlinux.lds
1136# used by scripts/Makefile.package
1137export KBUILD_ALLDIRS := $(sort $(filter-out arch/%,$(vmlinux-alldirs)) LICENSES arch include scripts tools)
1138
1139vmlinux-deps := $(KBUILD_LDS) $(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)
1140
1141# Recurse until adjust_autoksyms.sh is satisfied
1142PHONY += autoksyms_recursive
1143ifdef CONFIG_TRIM_UNUSED_KSYMS
1144# For the kernel to actually contain only the needed exported symbols,
1145# we have to build modules as well to determine what those symbols are.
1146# (this can be evaluated only once include/config/auto.conf has been included)
1147KBUILD_MODULES := 1
1148
1149autoksyms_recursive: descend modules.order
1150	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/adjust_autoksyms.sh \
1151	  "$(MAKE) -f $(srctree)/Makefile autoksyms_recursive"
1152endif
1153
1154autoksyms_h := $(if $(CONFIG_TRIM_UNUSED_KSYMS), include/generated/autoksyms.h)
1155
1156quiet_cmd_autoksyms_h = GEN     $@
1157      cmd_autoksyms_h = mkdir -p $(dir $@); \
1158			$(CONFIG_SHELL) $(srctree)/scripts/gen_autoksyms.sh $@
1159
1160$(autoksyms_h):
1161	$(call cmd,autoksyms_h)
1162
1163ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
1164
1165# Final link of vmlinux with optional arch pass after final link
1166cmd_link-vmlinux =                                                 \
1167	$(CONFIG_SHELL) $< "$(LD)" "$(KBUILD_LDFLAGS)" "$(LDFLAGS_vmlinux)";    \
1168	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
1169
1170vmlinux: scripts/link-vmlinux.sh autoksyms_recursive $(vmlinux-deps) FORCE
1171	+$(call if_changed_dep,link-vmlinux)
1172
1173targets := vmlinux
1174
1175# The actual objects are generated when descending,
1176# make sure no implicit rule kicks in
1177$(sort $(vmlinux-deps) $(subdir-modorder)): descend ;
1178
1179filechk_kernel.release = \
1180	echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1181
1182# Store (new) KERNELRELEASE string in include/config/kernel.release
1183include/config/kernel.release: FORCE
1184	$(call filechk,kernel.release)
1185
1186# Additional helpers built in scripts/
1187# Carefully list dependencies so we do not try to build scripts twice
1188# in parallel
1189PHONY += scripts
1190scripts: scripts_basic scripts_dtc
1191	$(Q)$(MAKE) $(build)=$(@)
1192
1193# Things we need to do before we recursively start building the kernel
1194# or the modules are listed in "prepare".
1195# A multi level approach is used. prepareN is processed before prepareN-1.
1196# archprepare is used in arch Makefiles and when processed asm symlink,
1197# version.h and scripts_basic is processed / created.
1198
1199PHONY += prepare archprepare
1200
1201archprepare: outputmakefile archheaders archscripts scripts include/config/kernel.release \
1202	asm-generic $(version_h) $(autoksyms_h) include/generated/utsrelease.h \
1203	include/generated/autoconf.h remove-stale-files
1204
1205prepare0: archprepare
1206	$(Q)$(MAKE) $(build)=scripts/mod
1207	$(Q)$(MAKE) $(build)=.
1208
1209# All the preparing..
1210prepare: prepare0
1211
1212PHONY += remove-stale-files
1213remove-stale-files:
1214	$(Q)$(srctree)/scripts/remove-stale-files
1215
1216# Support for using generic headers in asm-generic
1217asm-generic := -f $(srctree)/scripts/Makefile.asm-generic obj
1218
1219PHONY += asm-generic uapi-asm-generic
1220asm-generic: uapi-asm-generic
1221	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/asm \
1222	generic=include/asm-generic
1223uapi-asm-generic:
1224	$(Q)$(MAKE) $(asm-generic)=arch/$(SRCARCH)/include/generated/uapi/asm \
1225	generic=include/uapi/asm-generic
1226
1227# Generate some files
1228# ---------------------------------------------------------------------------
1229
1230# KERNELRELEASE can change from a few different places, meaning version.h
1231# needs to be updated, so this check is forced on all builds
1232
1233uts_len := 64
1234define filechk_utsrelease.h
1235	if [ `echo -n "$(KERNELRELEASE)" | wc -c ` -gt $(uts_len) ]; then \
1236	  echo '"$(KERNELRELEASE)" exceeds $(uts_len) characters' >&2;    \
1237	  exit 1;                                                         \
1238	fi;                                                               \
1239	echo \#define UTS_RELEASE \"$(KERNELRELEASE)\"
1240endef
1241
1242define filechk_version.h
1243	if [ $(SUBLEVEL) -gt 255 ]; then                                 \
1244		echo \#define LINUX_VERSION_CODE $(shell                 \
1245		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + 255); \
1246	else                                                             \
1247		echo \#define LINUX_VERSION_CODE $(shell                 \
1248		expr $(VERSION) \* 65536 + $(PATCHLEVEL) \* 256 + $(SUBLEVEL)); \
1249	fi;                                                              \
1250	echo '#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) +  \
1251	((c) > 255 ? 255 : (c)))';                                       \
1252	echo \#define LINUX_VERSION_MAJOR $(VERSION);                    \
1253	echo \#define LINUX_VERSION_PATCHLEVEL $(PATCHLEVEL);            \
1254	echo \#define LINUX_VERSION_SUBLEVEL $(SUBLEVEL)
1255endef
1256
1257$(version_h): PATCHLEVEL := $(or $(PATCHLEVEL), 0)
1258$(version_h): SUBLEVEL := $(or $(SUBLEVEL), 0)
1259$(version_h): FORCE
1260	$(call filechk,version.h)
1261
1262include/generated/utsrelease.h: include/config/kernel.release FORCE
1263	$(call filechk,utsrelease.h)
1264
1265PHONY += headerdep
1266headerdep:
1267	$(Q)find $(srctree)/include/ -name '*.h' | xargs --max-args 1 \
1268	$(srctree)/scripts/headerdep.pl -I$(srctree)/include
1269
1270# ---------------------------------------------------------------------------
1271# Kernel headers
1272
1273#Default location for installed headers
1274export INSTALL_HDR_PATH = $(objtree)/usr
1275
1276quiet_cmd_headers_install = INSTALL $(INSTALL_HDR_PATH)/include
1277      cmd_headers_install = \
1278	mkdir -p $(INSTALL_HDR_PATH); \
1279	rsync -mrl --include='*/' --include='*\.h' --exclude='*' \
1280	usr/include $(INSTALL_HDR_PATH)
1281
1282PHONY += headers_install
1283headers_install: headers
1284	$(call cmd,headers_install)
1285
1286PHONY += archheaders archscripts
1287
1288hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj
1289
1290PHONY += headers
1291headers: $(version_h) scripts_unifdef uapi-asm-generic archheaders archscripts
1292	$(if $(wildcard $(srctree)/arch/$(SRCARCH)/include/uapi/asm/Kbuild),, \
1293	  $(error Headers not exportable for the $(SRCARCH) architecture))
1294	$(Q)$(MAKE) $(hdr-inst)=include/uapi
1295	$(Q)$(MAKE) $(hdr-inst)=arch/$(SRCARCH)/include/uapi
1296
1297ifdef CONFIG_HEADERS_INSTALL
1298prepare: headers
1299endif
1300
1301PHONY += scripts_unifdef
1302scripts_unifdef: scripts_basic
1303	$(Q)$(MAKE) $(build)=scripts scripts/unifdef
1304
1305# ---------------------------------------------------------------------------
1306# Install
1307
1308# Many distributions have the custom install script, /sbin/installkernel.
1309# If DKMS is installed, 'make install' will eventually recurse back
1310# to this Makefile to build and install external modules.
1311# Cancel sub_make_done so that options such as M=, V=, etc. are parsed.
1312
1313quiet_cmd_install = INSTALL $(INSTALL_PATH)
1314      cmd_install = unset sub_make_done; $(srctree)/scripts/install.sh
1315
1316# ---------------------------------------------------------------------------
1317# Tools
1318
1319ifdef CONFIG_OBJTOOL
1320prepare: tools/objtool
1321endif
1322
1323ifdef CONFIG_BPF
1324ifdef CONFIG_DEBUG_INFO_BTF
1325prepare: tools/bpf/resolve_btfids
1326endif
1327endif
1328
1329PHONY += resolve_btfids_clean
1330
1331resolve_btfids_O = $(abspath $(objtree))/tools/bpf/resolve_btfids
1332
1333# tools/bpf/resolve_btfids directory might not exist
1334# in output directory, skip its clean in that case
1335resolve_btfids_clean:
1336ifneq ($(wildcard $(resolve_btfids_O)),)
1337	$(Q)$(MAKE) -sC $(srctree)/tools/bpf/resolve_btfids O=$(resolve_btfids_O) clean
1338endif
1339
1340# Clear a bunch of variables before executing the submake
1341ifeq ($(quiet),silent_)
1342tools_silent=s
1343endif
1344
1345tools/: FORCE
1346	$(Q)mkdir -p $(objtree)/tools
1347	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/
1348
1349tools/%: FORCE
1350	$(Q)mkdir -p $(objtree)/tools
1351	$(Q)$(MAKE) LDFLAGS= MAKEFLAGS="$(tools_silent) $(filter --j% -j,$(MAKEFLAGS))" O=$(abspath $(objtree)) subdir=tools -C $(srctree)/tools/ $*
1352
1353# ---------------------------------------------------------------------------
1354# Kernel selftest
1355
1356PHONY += kselftest
1357kselftest: headers
1358	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests run_tests
1359
1360kselftest-%: headers FORCE
1361	$(Q)$(MAKE) -C $(srctree)/tools/testing/selftests $*
1362
1363PHONY += kselftest-merge
1364kselftest-merge:
1365	$(if $(wildcard $(objtree)/.config),, $(error No .config exists, config your kernel first!))
1366	$(Q)find $(srctree)/tools/testing/selftests -name config | \
1367		xargs $(srctree)/scripts/kconfig/merge_config.sh -m $(objtree)/.config
1368	$(Q)$(MAKE) -f $(srctree)/Makefile olddefconfig
1369
1370# ---------------------------------------------------------------------------
1371# Devicetree files
1372
1373ifneq ($(wildcard $(srctree)/arch/$(SRCARCH)/boot/dts/),)
1374dtstree := arch/$(SRCARCH)/boot/dts
1375endif
1376
1377ifneq ($(dtstree),)
1378
1379%.dtb: dtbs_prepare
1380	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1381
1382%.dtbo: dtbs_prepare
1383	$(Q)$(MAKE) $(build)=$(dtstree) $(dtstree)/$@
1384
1385PHONY += dtbs dtbs_prepare dtbs_install dtbs_check
1386dtbs: dtbs_prepare
1387	$(Q)$(MAKE) $(build)=$(dtstree)
1388
1389# include/config/kernel.release is actually needed when installing DTBs because
1390# INSTALL_DTBS_PATH contains $(KERNELRELEASE). However, we do not want to make
1391# dtbs_install depend on it as dtbs_install may run as root.
1392dtbs_prepare: include/config/kernel.release scripts_dtc
1393
1394ifneq ($(filter dtbs_check, $(MAKECMDGOALS)),)
1395export CHECK_DTBS=y
1396dtbs: dt_binding_check
1397endif
1398
1399dtbs_check: dtbs
1400
1401dtbs_install:
1402	$(Q)$(MAKE) $(dtbinst)=$(dtstree) dst=$(INSTALL_DTBS_PATH)
1403
1404ifdef CONFIG_OF_EARLY_FLATTREE
1405all: dtbs
1406endif
1407
1408endif
1409
1410PHONY += scripts_dtc
1411scripts_dtc: scripts_basic
1412	$(Q)$(MAKE) $(build)=scripts/dtc
1413
1414ifneq ($(filter dt_binding_check, $(MAKECMDGOALS)),)
1415export CHECK_DT_BINDING=y
1416endif
1417
1418PHONY += dt_binding_check
1419dt_binding_check: scripts_dtc
1420	$(Q)$(MAKE) $(build)=Documentation/devicetree/bindings
1421
1422# ---------------------------------------------------------------------------
1423# Modules
1424
1425ifdef CONFIG_MODULES
1426
1427# By default, build modules as well
1428
1429all: modules
1430
1431# When we're building modules with modversions, we need to consider
1432# the built-in objects during the descend as well, in order to
1433# make sure the checksums are up to date before we record them.
1434ifdef CONFIG_MODVERSIONS
1435  KBUILD_BUILTIN := 1
1436endif
1437
1438# Build modules
1439#
1440# A module can be listed more than once in obj-m resulting in
1441# duplicate lines in modules.order files.  Those are removed
1442# using awk while concatenating to the final file.
1443
1444PHONY += modules
1445modules: $(if $(KBUILD_BUILTIN),vmlinux) modules_check modules_prepare
1446
1447cmd_modules_order = $(AWK) '!x[$$0]++' $(real-prereqs) > $@
1448
1449modules.order: $(subdir-modorder) FORCE
1450	$(call if_changed,modules_order)
1451
1452targets += modules.order
1453
1454# Target to prepare building external modules
1455PHONY += modules_prepare
1456modules_prepare: prepare
1457	$(Q)$(MAKE) $(build)=scripts scripts/module.lds
1458
1459export modules_sign_only :=
1460
1461ifeq ($(CONFIG_MODULE_SIG),y)
1462PHONY += modules_sign
1463modules_sign: modules_install
1464	@:
1465
1466# modules_sign is a subset of modules_install.
1467# 'make modules_install modules_sign' is equivalent to 'make modules_install'.
1468ifeq ($(filter modules_install,$(MAKECMDGOALS)),)
1469modules_sign_only := y
1470endif
1471endif
1472
1473modinst_pre :=
1474ifneq ($(filter modules_install,$(MAKECMDGOALS)),)
1475modinst_pre := __modinst_pre
1476endif
1477
1478modules_install: $(modinst_pre)
1479PHONY += __modinst_pre
1480__modinst_pre:
1481	@rm -rf $(MODLIB)/kernel
1482	@rm -f $(MODLIB)/source
1483	@mkdir -p $(MODLIB)/kernel
1484	@ln -s $(abspath $(srctree)) $(MODLIB)/source
1485	@if [ ! $(objtree) -ef  $(MODLIB)/build ]; then \
1486		rm -f $(MODLIB)/build ; \
1487		ln -s $(CURDIR) $(MODLIB)/build ; \
1488	fi
1489	@sed 's:^:kernel/:' modules.order > $(MODLIB)/modules.order
1490	@cp -f modules.builtin $(MODLIB)/
1491	@cp -f $(objtree)/modules.builtin.modinfo $(MODLIB)/
1492
1493endif # CONFIG_MODULES
1494
1495###
1496# Cleaning is done on three levels.
1497# make clean     Delete most generated files
1498#                Leave enough to build external modules
1499# make mrproper  Delete the current configuration, and all generated files
1500# make distclean Remove editor backup files, patch leftover files and the like
1501
1502# Directories & files removed with 'make clean'
1503CLEAN_FILES += include/ksym vmlinux.symvers modules-only.symvers \
1504	       modules.builtin modules.builtin.modinfo modules.nsdeps \
1505	       compile_commands.json .thinlto-cache
1506
1507# Directories & files removed with 'make mrproper'
1508MRPROPER_FILES += include/config include/generated          \
1509		  arch/$(SRCARCH)/include/generated .objdiff \
1510		  debian snap tar-install \
1511		  .config .config.old .version \
1512		  Module.symvers \
1513		  certs/signing_key.pem \
1514		  certs/x509.genkey \
1515		  vmlinux-gdb.py \
1516		  *.spec
1517
1518# clean - Delete most, but leave enough to build external modules
1519#
1520clean: rm-files := $(CLEAN_FILES)
1521
1522PHONY += archclean vmlinuxclean
1523
1524vmlinuxclean:
1525	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/link-vmlinux.sh clean
1526	$(Q)$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) clean)
1527
1528clean: archclean vmlinuxclean resolve_btfids_clean
1529
1530# mrproper - Delete all generated files, including .config
1531#
1532mrproper: rm-files := $(wildcard $(MRPROPER_FILES))
1533mrproper-dirs      := $(addprefix _mrproper_,scripts)
1534
1535PHONY += $(mrproper-dirs) mrproper
1536$(mrproper-dirs):
1537	$(Q)$(MAKE) $(clean)=$(patsubst _mrproper_%,%,$@)
1538
1539mrproper: clean $(mrproper-dirs)
1540	$(call cmd,rmfiles)
1541
1542# distclean
1543#
1544PHONY += distclean
1545
1546distclean: mrproper
1547	@find . $(RCS_FIND_IGNORE) \
1548		\( -name '*.orig' -o -name '*.rej' -o -name '*~' \
1549		-o -name '*.bak' -o -name '#*#' -o -name '*%' \
1550		-o -name 'core' -o -name tags -o -name TAGS -o -name 'cscope*' \
1551		-o -name GPATH -o -name GRTAGS -o -name GSYMS -o -name GTAGS \) \
1552		-type f -print | xargs rm -f
1553
1554
1555# Packaging of the kernel to various formats
1556# ---------------------------------------------------------------------------
1557
1558%src-pkg: FORCE
1559	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1560%pkg: include/config/kernel.release FORCE
1561	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
1562
1563# Brief documentation of the typical targets used
1564# ---------------------------------------------------------------------------
1565
1566boards := $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*_defconfig)
1567boards := $(sort $(notdir $(boards)))
1568board-dirs := $(dir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/*/*_defconfig))
1569board-dirs := $(sort $(notdir $(board-dirs:/=)))
1570
1571PHONY += help
1572help:
1573	@echo  'Cleaning targets:'
1574	@echo  '  clean		  - Remove most generated files but keep the config and'
1575	@echo  '                    enough build support to build external modules'
1576	@echo  '  mrproper	  - Remove all generated files + config + various backup files'
1577	@echo  '  distclean	  - mrproper + remove editor backup and patch files'
1578	@echo  ''
1579	@echo  'Configuration targets:'
1580	@$(MAKE) -f $(srctree)/scripts/kconfig/Makefile help
1581	@echo  ''
1582	@echo  'Other generic targets:'
1583	@echo  '  all		  - Build all targets marked with [*]'
1584	@echo  '* vmlinux	  - Build the bare kernel'
1585	@echo  '* modules	  - Build all modules'
1586	@echo  '  modules_install - Install all modules to INSTALL_MOD_PATH (default: /)'
1587	@echo  '  dir/            - Build all files in dir and below'
1588	@echo  '  dir/file.[ois]  - Build specified target only'
1589	@echo  '  dir/file.ll     - Build the LLVM assembly file'
1590	@echo  '                    (requires compiler support for LLVM assembly generation)'
1591	@echo  '  dir/file.lst    - Build specified mixed source/assembly target only'
1592	@echo  '                    (requires a recent binutils and recent build (System.map))'
1593	@echo  '  dir/file.ko     - Build module including final link'
1594	@echo  '  modules_prepare - Set up for building external modules'
1595	@echo  '  tags/TAGS	  - Generate tags file for editors'
1596	@echo  '  cscope	  - Generate cscope index'
1597	@echo  '  gtags           - Generate GNU GLOBAL index'
1598	@echo  '  kernelrelease	  - Output the release version string (use with make -s)'
1599	@echo  '  kernelversion	  - Output the version stored in Makefile (use with make -s)'
1600	@echo  '  image_name	  - Output the image name (use with make -s)'
1601	@echo  '  headers_install - Install sanitised kernel headers to INSTALL_HDR_PATH'; \
1602	 echo  '                    (default: $(INSTALL_HDR_PATH))'; \
1603	 echo  ''
1604	@echo  'Static analysers:'
1605	@echo  '  checkstack      - Generate a list of stack hogs'
1606	@echo  '  versioncheck    - Sanity check on version.h usage'
1607	@echo  '  includecheck    - Check for duplicate included header files'
1608	@echo  '  export_report   - List the usages of all exported symbols'
1609	@echo  '  headerdep       - Detect inclusion cycles in headers'
1610	@echo  '  coccicheck      - Check with Coccinelle'
1611	@echo  '  clang-analyzer  - Check with clang static analyzer'
1612	@echo  '  clang-tidy      - Check with clang-tidy'
1613	@echo  ''
1614	@echo  'Tools:'
1615	@echo  '  nsdeps          - Generate missing symbol namespace dependencies'
1616	@echo  ''
1617	@echo  'Kernel selftest:'
1618	@echo  '  kselftest         - Build and run kernel selftest'
1619	@echo  '                      Build, install, and boot kernel before'
1620	@echo  '                      running kselftest on it'
1621	@echo  '                      Run as root for full coverage'
1622	@echo  '  kselftest-all     - Build kernel selftest'
1623	@echo  '  kselftest-install - Build and install kernel selftest'
1624	@echo  '  kselftest-clean   - Remove all generated kselftest files'
1625	@echo  '  kselftest-merge   - Merge all the config dependencies of'
1626	@echo  '		      kselftest to existing .config.'
1627	@echo  ''
1628	@$(if $(dtstree), \
1629		echo 'Devicetree:'; \
1630		echo '* dtbs             - Build device tree blobs for enabled boards'; \
1631		echo '  dtbs_install     - Install dtbs to $(INSTALL_DTBS_PATH)'; \
1632		echo '  dt_binding_check - Validate device tree binding documents'; \
1633		echo '  dtbs_check       - Validate device tree source files';\
1634		echo '')
1635
1636	@echo 'Userspace tools targets:'
1637	@echo '  use "make tools/help"'
1638	@echo '  or  "cd tools; make help"'
1639	@echo  ''
1640	@echo  'Kernel packaging:'
1641	@$(MAKE) -f $(srctree)/scripts/Makefile.package help
1642	@echo  ''
1643	@echo  'Documentation targets:'
1644	@$(MAKE) -f $(srctree)/Documentation/Makefile dochelp
1645	@echo  ''
1646	@echo  'Architecture specific targets ($(SRCARCH)):'
1647	@$(or $(archhelp),\
1648		echo '  No architecture specific help defined for $(SRCARCH)')
1649	@echo  ''
1650	@$(if $(boards), \
1651		$(foreach b, $(boards), \
1652		printf "  %-27s - Build for %s\\n" $(b) $(subst _defconfig,,$(b));) \
1653		echo '')
1654	@$(if $(board-dirs), \
1655		$(foreach b, $(board-dirs), \
1656		printf "  %-16s - Show %s-specific targets\\n" help-$(b) $(b);) \
1657		printf "  %-16s - Show all of the above\\n" help-boards; \
1658		echo '')
1659
1660	@echo  '  make V=0|1 [targets] 0 => quiet build (default), 1 => verbose build'
1661	@echo  '  make V=2   [targets] 2 => give reason for rebuild of target'
1662	@echo  '  make O=dir [targets] Locate all output files in "dir", including .config'
1663	@echo  '  make C=1   [targets] Check re-compiled c source with $$CHECK'
1664	@echo  '                       (sparse by default)'
1665	@echo  '  make C=2   [targets] Force check of all c source with $$CHECK'
1666	@echo  '  make RECORDMCOUNT_WARN=1 [targets] Warn about ignored mcount sections'
1667	@echo  '  make W=n   [targets] Enable extra build checks, n=1,2,3 where'
1668	@echo  '		1: warnings which may be relevant and do not occur too often'
1669	@echo  '		2: warnings which occur quite often but may still be relevant'
1670	@echo  '		3: more obscure warnings, can most likely be ignored'
1671	@echo  '		e: warnings are being treated as errors'
1672	@echo  '		Multiple levels can be combined with W=12 or W=123'
1673	@echo  ''
1674	@echo  'Execute "make" or "make all" to build all targets marked with [*] '
1675	@echo  'For further info see the ./README file'
1676
1677
1678help-board-dirs := $(addprefix help-,$(board-dirs))
1679
1680help-boards: $(help-board-dirs)
1681
1682boards-per-dir = $(sort $(notdir $(wildcard $(srctree)/arch/$(SRCARCH)/configs/$*/*_defconfig)))
1683
1684$(help-board-dirs): help-%:
1685	@echo  'Architecture specific targets ($(SRCARCH) $*):'
1686	@$(if $(boards-per-dir), \
1687		$(foreach b, $(boards-per-dir), \
1688		printf "  %-24s - Build for %s\\n" $*/$(b) $(subst _defconfig,,$(b));) \
1689		echo '')
1690
1691
1692# Documentation targets
1693# ---------------------------------------------------------------------------
1694DOC_TARGETS := xmldocs latexdocs pdfdocs htmldocs epubdocs cleandocs \
1695	       linkcheckdocs dochelp refcheckdocs
1696PHONY += $(DOC_TARGETS)
1697$(DOC_TARGETS):
1698	$(Q)$(MAKE) $(build)=Documentation $@
1699
1700# Misc
1701# ---------------------------------------------------------------------------
1702
1703PHONY += scripts_gdb
1704scripts_gdb: prepare0
1705	$(Q)$(MAKE) $(build)=scripts/gdb
1706	$(Q)ln -fsn $(abspath $(srctree)/scripts/gdb/vmlinux-gdb.py)
1707
1708ifdef CONFIG_GDB_SCRIPTS
1709all: scripts_gdb
1710endif
1711
1712else # KBUILD_EXTMOD
1713
1714###
1715# External module support.
1716# When building external modules the kernel used as basis is considered
1717# read-only, and no consistency checks are made and the make
1718# system is not used on the basis kernel. If updates are required
1719# in the basis kernel ordinary make commands (without M=...) must be used.
1720
1721# We are always building only modules.
1722KBUILD_BUILTIN :=
1723KBUILD_MODULES := 1
1724
1725build-dirs := $(KBUILD_EXTMOD)
1726$(MODORDER): descend
1727	@:
1728
1729compile_commands.json: $(extmod_prefix)compile_commands.json
1730PHONY += compile_commands.json
1731
1732clean-dirs := $(KBUILD_EXTMOD)
1733clean: rm-files := $(KBUILD_EXTMOD)/Module.symvers $(KBUILD_EXTMOD)/modules.nsdeps \
1734	$(KBUILD_EXTMOD)/compile_commands.json $(KBUILD_EXTMOD)/.thinlto-cache
1735
1736PHONY += prepare
1737# now expand this into a simple variable to reduce the cost of shell evaluations
1738prepare: CC_VERSION_TEXT := $(CC_VERSION_TEXT)
1739prepare:
1740	@if [ "$(CC_VERSION_TEXT)" != "$(CONFIG_CC_VERSION_TEXT)" ]; then \
1741		echo >&2 "warning: the compiler differs from the one used to build the kernel"; \
1742		echo >&2 "  The kernel was built by: $(CONFIG_CC_VERSION_TEXT)"; \
1743		echo >&2 "  You are using:           $(CC_VERSION_TEXT)"; \
1744	fi
1745
1746PHONY += help
1747help:
1748	@echo  '  Building external modules.'
1749	@echo  '  Syntax: make -C path/to/kernel/src M=$$PWD target'
1750	@echo  ''
1751	@echo  '  modules         - default target, build the module(s)'
1752	@echo  '  modules_install - install the module'
1753	@echo  '  clean           - remove generated files in module directory only'
1754	@echo  ''
1755
1756# no-op for external module builds
1757PHONY += modules_prepare
1758
1759endif # KBUILD_EXTMOD
1760
1761# ---------------------------------------------------------------------------
1762# Modules
1763
1764PHONY += modules modules_install
1765
1766ifdef CONFIG_MODULES
1767
1768modules: modules_check
1769	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1770
1771PHONY += modules_check
1772modules_check: $(MODORDER)
1773	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh $<
1774
1775quiet_cmd_depmod = DEPMOD  $(MODLIB)
1776      cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
1777                   $(KERNELRELEASE)
1778
1779modules_install:
1780	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modinst
1781	$(call cmd,depmod)
1782
1783else # CONFIG_MODULES
1784
1785# Modules not configured
1786# ---------------------------------------------------------------------------
1787
1788modules modules_install:
1789	@echo >&2 '***'
1790	@echo >&2 '*** The present kernel configuration has modules disabled.'
1791	@echo >&2 '*** To use the module feature, please run "make menuconfig" etc.'
1792	@echo >&2 '*** to enable CONFIG_MODULES.'
1793	@echo >&2 '***'
1794	@exit 1
1795
1796endif # CONFIG_MODULES
1797
1798# Single targets
1799# ---------------------------------------------------------------------------
1800# To build individual files in subdirectories, you can do like this:
1801#
1802#   make foo/bar/baz.s
1803#
1804# The supported suffixes for single-target are listed in 'single-targets'
1805#
1806# To build only under specific subdirectories, you can do like this:
1807#
1808#   make foo/bar/baz/
1809
1810ifdef single-build
1811
1812# .ko is special because modpost is needed
1813single-ko := $(sort $(filter %.ko, $(MAKECMDGOALS)))
1814single-no-ko := $(filter-out $(single-ko), $(MAKECMDGOALS)) \
1815		$(foreach x, o mod, $(patsubst %.ko, %.$x, $(single-ko)))
1816
1817$(single-ko): single_modpost
1818	@:
1819$(single-no-ko): descend
1820	@:
1821
1822ifeq ($(KBUILD_EXTMOD),)
1823# For the single build of in-tree modules, use a temporary file to avoid
1824# the situation of modules_install installing an invalid modules.order.
1825MODORDER := .modules.tmp
1826endif
1827
1828PHONY += single_modpost
1829single_modpost: $(single-no-ko) modules_prepare
1830	$(Q){ $(foreach m, $(single-ko), echo $(extmod_prefix)$m;) } > $(MODORDER)
1831	$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost
1832
1833KBUILD_MODULES := 1
1834
1835export KBUILD_SINGLE_TARGETS := $(addprefix $(extmod_prefix), $(single-no-ko))
1836
1837# trim unrelated directories
1838build-dirs := $(foreach d, $(build-dirs), \
1839			$(if $(filter $(d)/%, $(KBUILD_SINGLE_TARGETS)), $(d)))
1840
1841endif
1842
1843ifndef CONFIG_MODULES
1844KBUILD_MODULES :=
1845endif
1846
1847# Handle descending into subdirectories listed in $(build-dirs)
1848# Preset locale variables to speed up the build process. Limit locale
1849# tweaks to this spot to avoid wrong language settings when running
1850# make menuconfig etc.
1851# Error messages still appears in the original language
1852PHONY += descend $(build-dirs)
1853descend: $(build-dirs)
1854$(build-dirs): prepare
1855	$(Q)$(MAKE) $(build)=$@ \
1856	single-build=$(if $(filter-out $@/, $(filter $@/%, $(KBUILD_SINGLE_TARGETS))),1) \
1857	need-builtin=1 need-modorder=1
1858
1859clean-dirs := $(addprefix _clean_, $(clean-dirs))
1860PHONY += $(clean-dirs) clean
1861$(clean-dirs):
1862	$(Q)$(MAKE) $(clean)=$(patsubst _clean_%,%,$@)
1863
1864clean: $(clean-dirs)
1865	$(call cmd,rmfiles)
1866	@find $(or $(KBUILD_EXTMOD), .) $(RCS_FIND_IGNORE) \
1867		\( -name '*.[aios]' -o -name '*.ko' -o -name '.*.cmd' \
1868		-o -name '*.ko.*' \
1869		-o -name '*.dtb' -o -name '*.dtbo' -o -name '*.dtb.S' -o -name '*.dt.yaml' \
1870		-o -name '*.dwo' -o -name '*.lst' \
1871		-o -name '*.su' -o -name '*.mod' -o -name '*.usyms' \
1872		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
1873		-o -name '*.lex.c' -o -name '*.tab.[ch]' \
1874		-o -name '*.asn1.[ch]' \
1875		-o -name '*.symtypes' -o -name 'modules.order' \
1876		-o -name '.tmp_*' \
1877		-o -name '*.c.[012]*.*' \
1878		-o -name '*.ll' \
1879		-o -name '*.gcno' \
1880		-o -name '*.*.symversions' \) -type f -print | xargs rm -f
1881
1882# Generate tags for editors
1883# ---------------------------------------------------------------------------
1884quiet_cmd_tags = GEN     $@
1885      cmd_tags = $(BASH) $(srctree)/scripts/tags.sh $@
1886
1887tags TAGS cscope gtags: FORCE
1888	$(call cmd,tags)
1889
1890# Script to generate missing namespace dependencies
1891# ---------------------------------------------------------------------------
1892
1893PHONY += nsdeps
1894nsdeps: export KBUILD_NSDEPS=1
1895nsdeps: modules
1896	$(Q)$(CONFIG_SHELL) $(srctree)/scripts/nsdeps
1897
1898# Clang Tooling
1899# ---------------------------------------------------------------------------
1900
1901quiet_cmd_gen_compile_commands = GEN     $@
1902      cmd_gen_compile_commands = $(PYTHON3) $< -a $(AR) -o $@ $(filter-out $<, $(real-prereqs))
1903
1904$(extmod_prefix)compile_commands.json: scripts/clang-tools/gen_compile_commands.py \
1905	$(if $(KBUILD_EXTMOD),,$(KBUILD_VMLINUX_OBJS) $(KBUILD_VMLINUX_LIBS)) \
1906	$(if $(CONFIG_MODULES), $(MODORDER)) FORCE
1907	$(call if_changed,gen_compile_commands)
1908
1909targets += $(extmod_prefix)compile_commands.json
1910
1911PHONY += clang-tidy clang-analyzer
1912
1913ifdef CONFIG_CC_IS_CLANG
1914quiet_cmd_clang_tools = CHECK   $<
1915      cmd_clang_tools = $(PYTHON3) $(srctree)/scripts/clang-tools/run-clang-tools.py $@ $<
1916
1917clang-tidy clang-analyzer: $(extmod_prefix)compile_commands.json
1918	$(call cmd,clang_tools)
1919else
1920clang-tidy clang-analyzer:
1921	@echo "$@ requires CC=clang" >&2
1922	@false
1923endif
1924
1925# Scripts to check various things for consistency
1926# ---------------------------------------------------------------------------
1927
1928PHONY += includecheck versioncheck coccicheck export_report
1929
1930includecheck:
1931	find $(srctree)/* $(RCS_FIND_IGNORE) \
1932		-name '*.[hcS]' -type f -print | sort \
1933		| xargs $(PERL) -w $(srctree)/scripts/checkincludes.pl
1934
1935versioncheck:
1936	find $(srctree)/* $(RCS_FIND_IGNORE) \
1937		-name '*.[hcS]' -type f -print | sort \
1938		| xargs $(PERL) -w $(srctree)/scripts/checkversion.pl
1939
1940coccicheck:
1941	$(Q)$(BASH) $(srctree)/scripts/$@
1942
1943export_report:
1944	$(PERL) $(srctree)/scripts/export_report.pl
1945
1946PHONY += checkstack kernelrelease kernelversion image_name
1947
1948# UML needs a little special treatment here.  It wants to use the host
1949# toolchain, so needs $(SUBARCH) passed to checkstack.pl.  Everyone
1950# else wants $(ARCH), including people doing cross-builds, which means
1951# that $(SUBARCH) doesn't work here.
1952ifeq ($(ARCH), um)
1953CHECKSTACK_ARCH := $(SUBARCH)
1954else
1955CHECKSTACK_ARCH := $(ARCH)
1956endif
1957checkstack:
1958	$(OBJDUMP) -d vmlinux $$(find . -name '*.ko') | \
1959	$(PERL) $(srctree)/scripts/checkstack.pl $(CHECKSTACK_ARCH)
1960
1961kernelrelease:
1962	@echo "$(KERNELVERSION)$$($(CONFIG_SHELL) $(srctree)/scripts/setlocalversion $(srctree))"
1963
1964kernelversion:
1965	@echo $(KERNELVERSION)
1966
1967image_name:
1968	@echo $(KBUILD_IMAGE)
1969
1970quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files)))
1971      cmd_rmfiles = rm -rf $(rm-files)
1972
1973# read saved command lines for existing targets
1974existing-targets := $(wildcard $(sort $(targets)))
1975
1976-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
1977
1978endif # config-build
1979endif # mixed-build
1980endif # need-sub-make
1981
1982PHONY += FORCE
1983FORCE:
1984
1985# Declare the contents of the PHONY variable as phony.  We keep that
1986# information in a variable so we can use it in if_changed and friends.
1987.PHONY: $(PHONY)
1988